PLATO (Programmed Logic for Automated Teaching Operations) was one of the earliest attempts to use computers as a tool for teaching rather than just storing and processing records. It originated at the University of Illinois and was later acquired and marketed by the Control Data Corporation (CDC).
When CDC went out of business, the intellectual assets of the PLATO system were broken up. Much of the content library returned to the University of Illinois. Other courseware assets were acquired by a Chicago-based organization led by William Roach, called The Roach Organization, later TRO Learning, and still later PLATO Learning Systems.
Rights to the visual-flowcharting authoring software were given to software engineer Michael Allen, who used it as the basis for a radically new kind of courseware authoring system for the then-new Macintosh computer, Authorware.
PLATO Learning Systems broke up in the early 2000s and its assets have been bought and sold several times. Some of the courseware is still commercially available, attesting to the durability of the original learning design.